Drill-grinding attachment for abrading-wheels.



B. L. MALLORY. DRILL GEINDING ATTACHMENT PoE ABEADING WHEELS.

APPLIOATION FILED MAB. 23. 1911.

Z SHEETS-SHEET 1.

(2 L a. MW@ "j Patented Feb. 4.1913.

B. L. MALLORY. DRILL GBINDING ATTACHMENT FOB. ABRADING WHEELS.APPLIOATION FILED 11.111. 2a. 1911.

1,052,073. Patented Feb. 4, 1913.

2 SHEETS-SHEET 2.

IWITNEQSES: [NVE/V701@ H. 2Q'. $.04.- w.; 4km?.

ATTI/ VUNrrED STATES vPAiii-intl: orEroE.

BONNIE L. MALLORY, br CLEVELAND, omo, AssrGNort or 'ONE-THIRD rro .FREDc. ELLAssER, or CLEVELAND, oHro.

DRILL-GRINDING ATTACHMENT Foa ABEApING-WHEELS.

speciacatibn er Letters Patent.

Patented Feb. 4,1913.

Application filed March 23, 1911. Serial No. 616,394.

To all whom it mayconcem:

Be it known that I, BONNIE L. MALLORY, a citizen of the United States,residing at Cleveland, in the county of Cuyahoga and State of Ohio, haveinvented a new and useful Improvement in Drill-Grinding Attachments forAbrading-Wheels, of which the following is a full, clear,and exactdescription, reference being had to the accompanying drawings.

This invention relates to drill-grinding attachments for emery wheels,the same having for its object, generally stated, the production of` adevice that is adapted to hold and guide the drill upon the convex orrounded surface of the emery wheel.

Further-objects of this invention are the production of a device ofthecharacter stated in which the drill holding attachments are so mountedand operated as to lproducethe'proper clearance at the rear of thecutting edges of the drill; in which'the drill may be convenientlyplaced for grindwhich .proper adjustments Amay be conveniently made forthe sizes and lengths of drills, and in which the parts are soconstructed as to be capable of Iconvenient operation and economicalmanufacture.

Qne structure in which the above'stated and other objects are attainedis shown in the accompanying drawings, in which- Figure 1 shows aportion of the wheel in side elevation with the grinding attachmentapplied thereto; Fig.,2 is a plan view of what is shown in Fig. 1, theupper parts4 of the holding rings for the grinding attachment beingbroken away; Fig. 3 is a view of the front of the attachment, or of theattachment as. viewed from the emery wheel; Fig. 4 is a sectional viewtake-n on the linev 4-4 of Fig. -2, and Fig. 5 is a perspective view ofparts of the grinding attachment, some of said partsbeing removed' fromtheir normal or assembled positions in order that they may be betterillustrated.

Taking up a detailed description of the invent-ion and employing thereferencecharacters foundV on the drawings, 1 represents an abradingwheel, which maybe made of emery or any other suitable material, saidwheel being supported upon suitable frame pieces 2,that are secured on asupport 3 of any desired character. Upon this same support, and inJfront of the convex edge of the mately sixty degrees.

wheel, is the support for the grinding attachment, said support beingshown as a socket member 4, although it -may be of any other suitablecharacter. A

Extending within the socket member 4, and held therein by a set screw 5,is theL stem 6 of ,the outer supporting ring 7 of the at tachment. Thisringis perfectly circular, and is providedwith ring plates 8 and 9 thatare secured to its sides and that 'project incoA wardly beyond the ringso as tol form a channel for confining a pair of half rings 10 and 11,said latterrings being, in effect, a single ring that is divided forconvenience in assembling only. Thel divided ring fits within the saidchannel with suiiicient looseness to permit it to turn freely within themain ring 7. As `appears from Fig. 3, the division line between the ringSections 10 and 11 is vertical and passes through the center ofcurvature of the main ring. At substantially their mid-points, the ringscctions are provided with holes 12, in which are journaled thetrunnioned ends 13 of a rocking cradle 14, the latter having`a-depending web 15 that preferably lies inthe samevertical plane as`the trunnions and has its lower edge curved concentrically with themain ring 7 This cradle also has what may be termed a trough portion 16,the same.

projecting beyond each side ofthe web and having its axis inclined withrespect to the axis of the web at an angle of approxiis a V-block 17,the lower surface of which is preferably flat, while the upper surfaceis provided with a V-shaped groove. This blockl rests upon the upper endof one or more screws 18, by means of which the block may be raised orlowered in the trough, for a purpose hereinafter stated. -For guidingthe block within the trough, the walls of both are grooved, the groovesof the trough being shown at 19 and those in the block being shown at20. When the arts are assembled, these grooves register and formverticalA seats for guide pins 2,1, see Fig. 4, said pins being partlyinthe trough and partly in the block. At the front end of the (trough 16I secure a gage 22, the same projecting in the direction of the emerywheel,

and then turning across the. rounded face of the latter, said gagevbeing for the purpose of correctly positioning the drill, the latter be-Within this trough indicated at 23. When thus positioned, the block israised or lowered, depending upon the manner in whichy it is alreadylset and the size of the drill to be ground, until the gage engages oneof the lutesof the drill, when the latter is in position vfor grinding.For forcing the drill against the emery wheel, I mount a set-screw 24 inan adjustable post 25 in such a manner that it may be screwed againstthe end of the drill shank, the post being slidably mounted on an arm 26that projects from the trough 16 and being held in its adjustedpositions by a set screw 27.

As is shown in Fig. 2, the drill 1s presented to the wheel at an angleof about thirty degrees from the normal at the'point of application. Ifthe drill were simply turned on its own axis, it would be ground to apoint, but there would be no clearance provided at the rear ofthecutting edges, such clearance being necessary to the cutting action o1the drill. If, on the other hand, the drill were held against rotationand were simply moved up and down by rocking the cradle 14, someclearance would be provided near the cutting edge, but the drill moreremote from such edge would not be sufficiently ground. It thereforebecomes necessary to give the drill both a rotary and a rocking movementin order to grind the same in the form of a spiral which recedes fromthe cutting edge, this being the best shape to grind the drill, since itcuts its way into the metal in a spiral direction. In order to give thedrill this double movement, I provide means for rotating or oscillatingthe cradle while it is being rocked on its trunnions 13. This meansconsists of a guide 28 that extends across the lower part of the ring 7at an angle of approximately twenty degrees, the same being secured,through its depending lugs 29, to bosses 30 on the stem 6 of theattachment. The upper surface of the guide 28 is preferably curved, withthea-'iris of the cradle as a center, and the web" of the lat-ter isprovided with a notch 31 into which the guide extends.

As will be seen by reference to Fig.,1, the

trunnions 13 are positioned slight-ly abovey the center of the wheel 1.When the cradle is in its normal position, as shown in said figure, theline of contact between the drill and the wheel is substantially in thecommon plane of the trunnion and the wheel axis. For accuratelyadjusting the cradle, a lug 32 is provided on the guide 28, and a setscrew 33 is projected through the lug into position to engage the cradleand thus limit the downward movement of the drill at the cutting line.For holding the cradle in normal position, a spring 34 is coiled aboutthe axis of the cradle, oneend of the same being attached to said axisand the noname other end to the adjacentsection of the divided ring.

TWhile it is believed that the operat-ion of the invention will beunderstood from the above description, it may be briefly statedasfollows: Assuming that the device is set for a three-quarter inch, andit is desired to grind a halt inch drill, the latter is placed in theV-block, which is then lifted by the set screw 18 until the gage 22rests against the drill and in the flute thereof. The post 25 is thenadjusted until the screw 24 abuts against the end of the drill shank. Bytheny bearing down on the post 25 or on the yarm 26, the cradle isrocked on its trunnions and the same is simultaneously turned in thebearing ring 7. This movement lifts the end of the drill that 4isagainst the wheel and, at the same time, twists the saine, therebycausing the wheel to grind the end of the drill in spiral shape. Thereare, of course, two cutting edges on the drill; and, after the abovestated operation has been repeated until that side of the drill issuiiicient-ly ground, the latter is turned over and the grinding iscontinued on the other side.v

Vhile the structure shown and described is very efficient, I realizethat many of the details may be varied without departing from the spiritof my invention, and I desire it to be understood that the followingclaims are not intended to be limited to such details any further thanis rendered necessary by the specilic terms therein employed.

Having thus described my invention what I claim as new and desire tosecure by Letters Patent is* 1. In a device of the character described,the combination with a supporting ring, of sliding members mountedwithin said ring, of a drill support within the ring and trunnioned-inthe sliding members and means for sliding said members within the iingwhen the drill support is rocked upon its trunnlons. f

2. In a device of the-'character described, the combination with asupporting ring, of a second ring within the supporting ring and adaptedfor turning therein, a cradle trunnioned in said second ring, a drillsupport carried by said cradle, and means tor turning the second ringwithin the supporting ring when the cradle is rocked upon its trunnions.

3. In a device of the character described., the combination with a mainring, of a second ring within the main ring and in the same planetherewith, said second ring being adapted to turn within the main ring,pivoted means trunnioned within the second ring, a drill supportingdevice carried by the said pivoted means in position for holding thedrill at an angle to t-he plane of 4. In a device of the characterdescribed, the combination with a main ring. of a second ring withinthe' main ring and in the same plane therewith, said second ring beingadapted to slidewithin'the'main ring, a cradle extending across thesecond ring and trunnioned therein, a trough member on said cradle, aV-block within said trough' member, said block being adapted to supporta drill for grinding,means for raising or lowering the block within "thetrough member, and a guide stationarily mounted with respect to thecradle and engaging with the latter so as to turn it and s he drill asthe cradle is rocked upon its trun ions.

5. In a device of the character descr'bed, the combination with a mainring, of 1*lieans for holding said ring stationary w` respect toanabrading wheel, a second ring within the main ring and in the same planetherewith, said ring being adapted to turn within the' main ring, acradle extending across the second ring and trunnioned in the latter, atrough member on the cradle, a V- block in the trough member, means forguiding said block within said member, means for raising and lowerin theblock within the member so asl to position the drill with respect to theabrading wheel, means for eeding'the drill longitudinally against thewheel, an adjustable stop, s ring means for normally holding the cra leagainst said stop, and a guide inclined to the axis of the cradle andengaging the latter so as toturn it and the second ring within the mainring when the cradle is rocked on its trunnions.

6. In a device of the character described,

'the combination with a main ring, means .for holding said ringstationary in front of the convex Asurface of an abrading wheel, asecond ring within the main-ring and in the same plane therewith, saidsecond ring being adapted. to slide within' the main ring, a cradleextending across the secondring and being trunnioned at its ends in saidring, a

trough member on said cradle, said member` having its axis at an angleto the axis of the cradle, a drill support within said trough member,means for adjusting said support for diierent dia-meters of drllls, agage iinger on the trough member for engaging the drill when the saidsupport isadjusted, and a guide stationarily mounted with respect to thecradle and engaging the latterfor sliding the second ring wlthin themain ring when the cradle is rocked on its trunnions.

7'. In a device of thecharaeterA described, the combination with a mainring, said ring being statimiarilysupported with respect to the convexsurface of an abradlng wheel, of

a second ring slidingly mounted within the main ring and in the sameplane therewith, retainin ring members secured to the main ring anprojecting inwardly to hold .the second ring in position, a cradletrunnioned in the second ring, an adjustable stop, a spring engaging thesecond ring and the cradle and being adapted' to normally vhold thecradle against said stop, a stationary guideextending at an angle to theaxis of the cradle and engaging the latter so as' to'slide the secondring within the main ring when the cradle is rocked on its trunnions,and means carried by the cradle for supporting a drill, said meansholding the drill at an angle to the said guide and to the axis of thecradle.

8. In a deviceof` the character described, the combination with a mainring that is stationarily supported in front of the convex surface of anabrading wheel, of a lsecond ring within the main ring and in the sameplane therewith, the second ring being adapted to slide within the mainring, a cradle extending across the second rin and being trunnionedtherein, said cradle avin a trough member thereon, a V-blockl wit in thetrough member, said block being adapted to support a drillyfor grinding,pin guides 'for said block, means for adjusting the block along thepinsand within the said member,

an arm on the said. trough member, a post Y adjustably mounted on thesaid arm, a screw carried by said `post and adapted to engage the shankend of the drill for forcing the latteragainst the abrading wheel, agage finger carried by the trough member and adapted to engage thelatter, sa id guide being inclined with respect to the axis of thecradle so as to cause the second ring'to turn i.

within the main ring when the cradle is rocked on its trunnion.

9. In a device of the character described,

the combination with a main ring that is stationarily secured withrespect to the convex surface of. an -abrading wheel, of as'ccond ringwithin the mam ring and in the same planetherewith, saidk second ringbeing` adapted to slide within the main ring, devices secured to themain ring for retaining the second ring in position, a cradleextendingacross the second rin and being journaled therein, an adjusts.le stop, a spring engagin with the second ring and with the cradleor`ho1dingv the latter against said e stop, aiguide stationarilymountedvwith respect to the cradle and engaging t said guide beinginclined resric axis of the cradle so as toturn the second ring withinlthe main-ring when the 4cradle isv rocked on its trunnions, a troughmember on the cradle, saidgmember extending at an an-- gle totheguide'and to the axis of the cradle,

a V-block within-the trough member, pin. i

uidesw-ithin the said member. and within the block for guiding thelatter, a screw CTX passing through the bottom. of the trough andabutting against the tl-block for adjusting the latter in the trough,a11 arm extend- Lomme gagement by the drill as the block is adjust 10ed, as and for the purpose specified.

1n testimony whereof, I hereunto aix my ing from the trough, a postadjustably signature in the presence of two Witnesses.

mounted on said arm, a screw carried by the post in position forengagement with the shank end of the drill as it lies in the V- biock,and a gage finger secured to the trough and extending into position foren- BUNNE L. MALLRY. Witnesses;

BRENNAN B. WEST, MANSFIELD ML WEST.

